1. Field of the Invention
The present invention relates to a check system for a control board provided with a micro-computer and, more particularly, to a check system for checking the abnormal state of wirings and interfaces disposed between the respective input/output connectors of the control board and the corresponding input/output terminals of the micro-computer.
2. Description of the Prior Art
There have been proposed many check systems for checking the abnormal state of the control board provided with the micro-computer by the employment of a checker to be connected between the control board and micro-computer before the operation thereof.
Check systems are largely divided into two types; one of which is for confirming whether or not certain signal levels of inputs/outputs exist by checking a given sequence with respect to the normal functions of the control board being actuated in the actual operation, and the other by the employment of a check program provided for operating the checker of simple construction within the main program for operating the micro-computer provided on the control board, both of which are difficult to present in a checker of standard construction capable of being applied to the various kinds of control boards.
For instance, U.S. Pat. No. 4,200,224 discloses a method and a system for isolating faults in a microprocessor and a machine controlled by the microprocessor, wherein the operation of the machine to be controlled by the microprocessor and the parts of the microprocessor are checked by the employment of a test program stored in the microprocessor. This system is characterized in that it tests a unit of the machine and microcomputer, both being connected with each other, and applies the test in broad areas including the machine. Therefore, this system has a disadvantage in the application of checking lines disposed between the connectors of the control board and the terminals of the microprocessor after removing the control board provided with the microprocessor from the machine. Also, for checking all the ports of the microprocessor to be connected with the checker, it is necessary to provide connectors or pins corresponding in number to all the ports therefore which increases the size of the control board. In addition, it is necessary to provide switches and light emitting diodes within the checker, whereby the standardization for the arrangement of the checker is difficult in practical use.